Targacept (NASDAQ:TRGT) Chairman of the Board Mark Skaletsky has resigned from the board effective immediately, the drug developer disclosed in a securities filing Thursday.

The resignation is for unspecified personal reasons and not the result of any disagreement between the company and Skaletsky, the company said in the filing.

Winston-Salem-based Targacept develops drugs that target neuronal nicotinic receptors. The company does not yet have any Food and Drug Administration-approved drugs but is pursuing potential treatments in schizophrenia, overactive bladder and Alzheimer’s disease. A depression drug candidate that had been the company’s lead compound failed in phase III clinical trials last year.

That failure sparked a reorganization at Targacept, including layoffs and the departure of former CEO Don deBethizy. Following the departure of deBethizy, Skaletsky led a a four-person committee, called the “Office of the Chairman,” that oversaw the company.

Targacept shares closed Friday at $4.90, up 22 cents compared to Thursday’s closing price.